How long should a temporary inbox live?
17 July 2026 · 3 min read
Too short and the code arrives after the inbox has expired. Too long and you have quietly built permanent storage of other people’s mail.
What actually drives the number
- Verification mail usually arrives in seconds, occasionally in minutes.
- Some senders queue for an hour on first contact with an unknown domain.
- People walk away mid-signup and come back.
An hour with the option to extend covers nearly everything. What matters more than the number is that expiry is enforced: a sweep that actually deletes, and a health check that fails if anything is overdue. "We delete eventually" is not a retention policy.
More on guides
How to read email headers without guessing
Received lines read bottom to top, Authentication-Results is the verdict, and the timestamps tell you who was slow.
Use a subdomain, unless you really mean it
Pointing your main domain’s MX at a new service takes over all of its mail. A subdomain gets you the same feature with none of the risk.
Getting to DMARC p=reject without breaking your mail
The policy is the easy part. Finding everything that sends as you is the work.